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1.
PLoS One ; 19(4): e0299292, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630666

RESUMO

Recent advances in interdisciplinary archaeological research in Arabia have focused on the evolution and historical development of regional human populations as well as the diverse patterns of cultural change, migration, and adaptations to environmental fluctuations. Obtaining a comprehensive understanding of cultural developments such as the emergence and lifeways of Neolithic groups has been hindered by the limited preservation of stratified archaeological assemblages and organic remains, a common challenge in arid environments. Underground settings like caves and lava tubes, which are prevalent in Arabia but which have seen limited scientific exploration, offer promising opportunities for addressing these issues. Here, we report on an archaeological excavation and a related survey at and around Umm Jirsan lava tube in the Harrat Khaybar, north-western Saudi Arabia. Our results reveal repeated phases of human occupation of the site ranging from at least the Neolithic through to the Chalcolithic/Bronze Age. Pastoralist use of the lava tube and surrounding landscape is attested in rock art and faunal records, suggesting that Umm Jirsan was situated along a pastoral route linking key oases. Isotopic data indicates that herbivores primarily grazed on wild grasses and shrubs rather than being provided with fodder, while humans had a diet consistently high in protein but with increasing consumption of C3 plants through-time, perhaps related to the emergence of oasis agriculture. While underground and naturally sheltered localities are globally prominent in archaeology and Quaternary science, our work represents the first such combined records for Saudi Arabia and highlight the potential for interdisciplinary studies in caves and lava tubes.


Assuntos
Cavernas , Hominidae , Humanos , Animais , Arábia , Arábia Saudita , Arqueologia/métodos , Ocupações
2.
Artigo em Inglês | MEDLINE | ID: mdl-38597725

RESUMO

Extreme heat caused by climate change is increasing transmission of infectious diseases resulting in a sharp rise in heat-related illness and mortality. Understanding mechanistic link between heat, inflammation and disease is thus important for public health. Thermal hyperpnea, and consequent respiratory alkalosis is crucial in febrile seizures and convulsions induced by heat stress in humans. Here we address what causes thermal hyperpnea in neonates and how is it affected by inflammation. TRPV1, a heat-activated channel is sensitized by inflammation and modulates breathing, and thus may play a key role. To investigate whether inflammatory sensitization of TRPV1 modifies neonatal ventilatory responses to heat stress, leading to respiratory alkalosis and an increased susceptibility to hyperthermic seizures we treated neonatal rats with bacterial lipopolysaccharide, and breathing, arterial pH, in-vitro vagus nerve activity, and seizure susceptibility were assessed during heat stress in the presence or absence of a TRPV1 antagonist (AMG-9810) or shRNA-mediated TRPV1 suppression. Lipopolysaccharide-induced inflammatory preconditioning lowered the threshold temperature and latency of hyperthermic seizures. This was accompanied by increased tidal volume, minute ventilation, expired CO2, and arterial pH (alkalosis). Lipopolysaccharide exposure also elevated vagal spiking and intracellular calcium levels in response to hyperthermia. TRPV1 inhibition with AMG-9810 or shRNA reduced the lipopolysaccharide-induced susceptibility to hyperthermic seizures and altered the breathing pattern to fast shallow breaths (tachypnea), making each breath less efficient and restoring arterial pH. These results indicate that inflammation exacerbates thermal hyperpnea-induced respiratory alkalosis associated with increased susceptibility to hyperthermic seizures, primarily mediated by TRPV1 localized to vagus neurons.

3.
Chem Sci ; 15(13): 4969-4980, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38550701

RESUMO

The selective α,ß-desaturation of cyclic carbonyl compounds, which are found in the core of many steroid and bioactive molecules, using green chemistry is highly desirable. To achieve this task, we have for the first time described and solved the de novo structure of a member of the cyclohexanone dehydrogenase class of enzymes. The breadth of substrate specificity was investigated by assaying the cyclohexanone dehydrogenase, from Alicycliphilus denitrificans, against several cyclic ketones, lactones and lactams. To investigate substrate binding, a catalytic variant, Y195F, was generated and used to obtain a crystallographic complex with the natural substrate, cyclohexanone. This revealed substrate-active site interactions, as well as the proximity of the cofactor, flavin adenine dinucleotide, and enabled us to propose a mechanistic function to key amino acids. We then used molecular dynamic simulations to guide design to add functionality to the cyclohexanone dehydrogenase enzyme. The resulting W113A variant had overall improved enzyme activity and substrate scope, i.e., accepting the bulkier carbonyl compound, dihydrocoumarin. Structural analysis of the W113A variant revealed a broader, more open active site, which helped explain the modified substrate specificity. This work paves the way for future bespoke regioselective α,ß-desaturation in the synthesis of important bioactive molecules via rational enzyme engineering.

4.
Health Technol Assess ; 28(14): 1-101, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38512064

RESUMO

Background: Neutropenic sepsis is a common complication of systemic anticancer treatment. There is variation in practice in timing of switch to oral antibiotics after commencement of empirical intravenous antibiotic therapy. Objectives: To establish the clinical and cost effectiveness of early switch to oral antibiotics in patients with neutropenic sepsis at low risk of infective complications. Design: A randomised, multicentre, open-label, allocation concealed, non-inferiority trial to establish the clinical and cost effectiveness of early oral switch in comparison to standard care. Setting: Nineteen UK oncology centres. Participants: Patients aged 16 years and over receiving systemic anticancer therapy with fever (≥ 38°C), or symptoms and signs of sepsis, and neutropenia (≤ 1.0 × 109/l) within 24 hours of randomisation, with a Multinational Association for Supportive Care in Cancer score of ≥ 21 and receiving intravenous piperacillin/tazobactam or meropenem for < 24 hours were eligible. Patients with acute leukaemia or stem cell transplant were excluded. Intervention: Early switch to oral ciprofloxacin (750 mg twice daily) and co-amoxiclav (625 mg three times daily) within 12-24 hours of starting intravenous antibiotics to complete 5 days treatment in total. Control was standard care, that is, continuation of intravenous antibiotics for at least 48 hours with ongoing treatment at physician discretion. Main outcome measures: Treatment failure, a composite measure assessed at day 14 based on the following criteria: fever persistence or recurrence within 72 hours of starting intravenous antibiotics; escalation from protocolised antibiotics; critical care support or death. Results: The study was closed early due to under-recruitment with 129 patients recruited; hence, a definitive conclusion regarding non-inferiority cannot be made. Sixty-five patients were randomised to the early switch arm and 64 to the standard care arm with subsequent intention-to-treat and per-protocol analyses including 125 (intervention n = 61 and control n = 64) and 113 (intervention n = 53 and control n = 60) patients, respectively. In the intention-to-treat population the treatment failure rates were 14.1% in the control group and 24.6% in the intervention group, difference = 10.5% (95% confidence interval 0.11 to 0.22). In the per-protocol population the treatment failure rates were 13.3% and 17.7% in control and intervention groups, respectively; difference = 3.7% (95% confidence interval 0.04 to 0.148). Treatment failure predominantly consisted of persistence or recurrence of fever and/or physician-directed escalation from protocolised antibiotics with no critical care admissions or deaths. The median length of stay was shorter in the intervention group and adverse events reported were similar in both groups. Patients, particularly those with care-giving responsibilities, expressed a preference for early switch. However, differences in health-related quality of life and health resource use were small and not statistically significant. Conclusions: Non-inferiority for early oral switch could not be proven due to trial under-recruitment. The findings suggest this may be an acceptable treatment strategy for some patients who can adhere to such a treatment regimen and would prefer a potentially reduced duration of hospitalisation while accepting increased risk of treatment failure resulting in re-admission. Further research should explore tools for patient stratification for low-risk de-escalation or ambulatory pathways including use of biomarkers and/or point-of-care rapid microbiological testing as an adjunct to clinical decision-making tools. This could include application to shorter-duration antimicrobial therapy in line with other antimicrobial stewardship studies. Trial registration: This trial is registered as ISRCTN84288963. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 13/140/05) and is published in full in Health Technology Assessment; Vol. 28, No. 14. See the NIHR Funding and Awards website for further award information.


Neutropenic sepsis, or infection with a low white blood cell count, can occur following cancer treatment. Usually patients receive treatment with intravenous antibiotics (antibiotics delivered into a vein) for two or more days. Patients at low risk of complications from their infection may be able to have a shorter period of intravenous antibiotics benefitting both patients and the NHS. The trial compared whether changing from intravenous to oral antibiotics (antibiotics taken by mouth as tablets or liquid) 12­24 hours after starting antibiotic treatment ('early switch') is as effective as usual care. Patients could take part if they had started intravenous antibiotics for low-risk neutropenic sepsis. Patients were randomly allocated to 'early switch' or to usual care. The main outcome measured was treatment failure. Treatment failure happened if fever persisted or recurred despite antibiotics, if patients needed to change antibiotics, if they needed to be re-admitted to hospital or needed to be admitted to intensive care within 14 days or died. We had originally intended that 628 patients would take part, but after review of the design of the study the number needed to take part was revised to 230. We were not able to complete the trial as planned as unfortunately only 129 patients took part. As the trial was smaller than expected we were not able to draw conclusions as to whether 'early switch' is no less effective than usual care. Our findings suggest that 'early switch' might result in a shorter time in hospital initially; however, treatment failure was more likely to occur, meaning some patients had to return to hospital for further antibiotics. There were no differences in side effects and no serious complications from treatment or treatment failure (such as intensive care admission or death) among the 65 patients in the 'early switch' group. Patients were satisfied with 'early switch'. Early switch may be a treatment option for some patients with low-risk neutropenic sepsis who would prefer a shorter duration of hospital admission but accept a risk of needing hospital re-admission.


Assuntos
Neoplasias , Neutropenia , Humanos , Qualidade de Vida , Neutropenia/tratamento farmacológico , Neoplasias/complicações , Administração Oral , Antibacterianos/uso terapêutico
5.
New Phytol ; 242(3): 1257-1274, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38481385

RESUMO

Plant pathogenic fungi elaborate numerous detoxification strategies to suppress host reactive oxygen species (ROS), but their coordination is not well-understood. Here, we show that Sirt5-mediated protein desuccinylation in Magnaporthe oryzae is central to host ROS detoxification. SIRT5 encodes a desuccinylase important for virulence via adaptation to host oxidative stress. Quantitative proteomics analysis identified a large number of succinylated proteins targeted by Sirt5, most of which were mitochondrial proteins involved in oxidative phosphorylation, TCA cycle, and fatty acid oxidation. Deletion of SIRT5 resulted in hypersuccinylation of detoxification-related enzymes, and significant reduction in NADPH : NADP+ and GSH : GSSG ratios, disrupting redox balance and impeding invasive growth. Sirt5 desuccinylated thioredoxin Trx2 and glutathione peroxidase Hyr1 to activate their enzyme activity, likely by affecting proper folding. Altogether, this work demonstrates the importance of Sirt5-mediated desuccinylation in controlling fungal process required for detoxifying host ROS during M. oryzae infection.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Espécies Reativas de Oxigênio/metabolismo , Lisina/metabolismo , Estresse Oxidativo , Ascomicetos/metabolismo , Proteínas Fúngicas/metabolismo , Oryza/metabolismo , Doenças das Plantas/microbiologia
6.
Phys Med Rehabil Clin N Am ; 35(2): 445-462, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38514229

RESUMO

Pain can be a significant barrier to a stroke survivors' functional recovery and can also lead to a decreased quality of life. Common pain conditions after stroke include headache, musculoskeletal pain, spasticity-related pain, complex regional pain syndrome, and central poststroke pain. This review investigates the evidence of diagnostic and management guidelines for various pain syndromes after stroke and identifies opportunities for future research to advance the field of poststroke pain.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Qualidade de Vida , Dor , Acidente Vascular Cerebral/complicações , Cefaleia , Espasticidade Muscular/etiologia
7.
Eur J Appl Physiol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489034

RESUMO

With ascent to high altitude (HA), compensatory increases in cerebral blood flow and oxygen delivery must occur to preserve cerebral metabolism and consciousness. We hypothesized that this compensation in cerebral blood flow and oxygen delivery preserves tolerance to simulated hemorrhage (via lower body negative pressure, LBNP), such that tolerance is similar during sustained exposure to HA vs. low altitude (LA). Healthy humans (4F/4 M) participated in LBNP protocols to presyncope at LA (1130 m) and 5-7 days following ascent to HA (3800 m). Internal carotid artery (ICA) blood flow, cerebral delivery of oxygen (CDO2) through the ICA, and cerebral tissue oxygen saturation (ScO2) were determined. LBNP tolerance was similar between conditions (LA: 1276 ± 304 s vs. HA: 1208 ± 306 s; P = 0.58). Overall, ICA blood flow and CDO2 were elevated at HA vs. LA (P ≤ 0.01) and decreased with LBNP under both conditions (P < 0.0001), but there was no effect of altitude on ScO2 responses (P = 0.59). Thus, sustained exposure to hypobaric hypoxia did not negatively impact tolerance to simulated hemorrhage. These data demonstrate the robustness of compensatory physiological mechanisms that preserve human cerebral blood flow and oxygen delivery during sustained hypoxia, ensuring cerebral tissue metabolism and neuronal function is maintained.

8.
BMC Genomics ; 25(1): 122, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287261

RESUMO

BACKGROUND: Cancers exhibit complex transcriptomes with aberrant splicing that induces isoform-level differential expression compared to non-diseased tissues. Transcriptomic profiling using short-read sequencing has utility in providing a cost-effective approach for evaluating isoform expression, although short-read assembly displays limitations in the accurate inference of full-length transcripts. Long-read RNA sequencing (Iso-Seq), using the Pacific Biosciences (PacBio) platform, can overcome such limitations by providing full-length isoform sequence resolution which requires no read assembly and represents native expressed transcripts. A constraint of the Iso-Seq protocol is due to fewer reads output per instrument run, which, as an example, can consequently affect the detection of lowly expressed transcripts. To address these deficiencies, we developed a concatenation workflow, PacBio Full-Length Isoform Concatemer Sequencing (PB_FLIC-Seq), designed to increase the number of unique, sequenced PacBio long-reads thereby improving overall detection of unique isoforms. In addition, we anticipate that the increase in read depth will help improve the detection of moderate to low-level expressed isoforms. RESULTS: In sequencing a commercial reference (Spike-In RNA Variants; SIRV) with known isoform complexity we demonstrated a 3.4-fold increase in read output per run and improved SIRV recall when using the PB_FLIC-Seq method compared to the same samples processed with the Iso-Seq protocol. We applied this protocol to a translational cancer case, also demonstrating the utility of the PB_FLIC-Seq method for identifying differential full-length isoform expression in a pediatric diffuse midline glioma compared to its adjacent non-malignant tissue. Our data analysis revealed increased expression of extracellular matrix (ECM) genes within the tumor sample, including an isoform of the Secreted Protein Acidic and Cysteine Rich (SPARC) gene that was expressed 11,676-fold higher than in the adjacent non-malignant tissue. Finally, by using the PB_FLIC-Seq method, we detected several cancer-specific novel isoforms. CONCLUSION: This work describes a concatenation-based methodology for increasing the number of sequenced full-length isoform reads on the PacBio platform, yielding improved discovery of expressed isoforms. We applied this workflow to profile the transcriptome of a pediatric diffuse midline glioma and adjacent non-malignant tissue. Our findings of cancer-specific novel isoform expression further highlight the importance of long-read sequencing for characterization of complex tumor transcriptomes.


Assuntos
Glioma , Transcriptoma , Humanos , Criança , Perfilação da Expressão Gênica/métodos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Splicing de RNA , Análise de Sequência de RNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos
9.
Nat Commun ; 15(1): 506, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218885

RESUMO

Antimicrobial resistance (AMR) and healthcare associated infections pose a significant threat globally. One key prevention strategy is to follow antimicrobial stewardship practices, in particular, to maximise targeted oral therapy and reduce the use of indwelling vascular devices for intravenous (IV) administration. Appreciating when an individual patient can switch from IV to oral antibiotic treatment is often non-trivial and not standardised. To tackle this problem we created a machine learning model to predict when a patient could switch based on routinely collected clinical parameters. 10,362 unique intensive care unit stays were extracted and two informative feature sets identified. Our best model achieved a mean AUROC of 0.80 (SD 0.01) on the hold-out set while not being biased to individuals protected characteristics. Interpretability methodologies were employed to create clinically useful visual explanations. In summary, our model provides individualised, fair, and interpretable predictions for when a patient could switch from IV-to-oral antibiotic treatment. Prospectively evaluation of safety and efficacy is needed before such technology can be applied clinically.


Assuntos
Antibacterianos , Aprendizado de Máquina , Humanos , Antibacterianos/uso terapêutico , Administração Intravenosa , Administração Oral , Tomada de Decisões
10.
Anal Methods ; 16(4): 558-565, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38189092

RESUMO

Background: The optimization of antimicrobial dosing plays a crucial role in improving the likelihood of achieving therapeutic success while reducing the risks associated with toxicity and antimicrobial resistance. Probenecid has shown significant potential in enhancing the serum exposure of phenoxymethylpenicillin, thereby allowing for lower doses of phenoxymethylpenicillin to achieve similar pharmacokinetic/pharmacodynamic (PK/PD) targets. We developed a triple quadrupole liquid chromatography mass spectrometry (TQ LC/MS) analysis of, phenoxymethylpenicillin, benzylpenicillin and probenecid using benzylpenicillin-d7 and probenecid-d14 as IS in single low-volumes of human serum, with improved limit of quantification to support therapeutic drug monitoring. Methods: Sample clean-up was performed by protein precipitation using acetonitrile. Reverse phase chromatography was performed using TQ LC/MS. The mobile phase consisted of 55% methanol in water + 0.1% formic acid, with a flow rate of 0.4 mL min-1. Antibiotic stability was assessed at different temperatures. Results: Chromatographic separation was achieved within 2 minutes, allowing simultaneous measurement of phenoxymethylpenicillin, benzylpenicillin and probenecid in a single 15 µL blood sample. Validation indicated linearity over the range 0.0015-10 mg L-1, with accuracy of 96-102% and a LLOQ of 0.01 mg L-1. All drugs demonstrated good stability under different storage conditions. Conclusion: The developed method is simple, rapid, accurate and clinically applicable for the quantification of phenoxymethylpenicillin, benzylpenicillin and probenecid in tandem.


Assuntos
Penicilina V , Probenecid , Humanos , Probenecid/farmacologia , Espectrometria de Massas em Tandem/métodos , Antibacterianos/farmacologia , Penicilina G
11.
Phys Chem Chem Phys ; 26(4): 2877-2886, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38048065

RESUMO

Extractant design in liquid-liquid extraction (LLE) is a research frontier of metal ion separations that typically focuses on the direct extractant-metal interactions. However, a more detailed understanding of energetic drivers of separations beyond primary metal coordination is often lacking, including the role of solvent in the extractant phase. In this work, we propose a new mechanism for enhancing metal-complexant energetics with nanostructured solvents. Using molecular dynamics simulations with umbrella sampling, we find that the organic solvent can reshape the energetics of the extractant's intramolecular conformational landscape. We calculate free energy profiles of different conformations of a representative bidentate extractant, n-octyl(phenyl)-N,N-diisobutyl carbamoyl methyl phosphinoxide (CMPO), in four different solvents: dodecane, tributyl phosphate (TBP), and dry and wet ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][Tf2N]). By promoting reorganization of the extractant molecule into its binding conformation, our findings reveal how particular solvents can ameliorate this unfavorable step of the metal separation process. In particular, the charge alternating nanodomains formed in ILs substantially reduce the free energy penalty associated with extractant reorganization. Importantly, using alchemical free energy calculations, we find that this stabilization persists even when we explicitly include the extracted cation. These findings provide insight into the energetic drivers of metal ion separations and potentially suggest a new approach to designing effective separations using a molecular-level understanding of solvent effects.

12.
Clin Microbiol Infect ; 30(1): 92-99, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37517522

RESUMO

OBJECTIVES: To determine whether early switch to oral antibiotic treatment in adults with neutropenic sepsis at low risk of complications is non-inferior to switching later. METHODS: This non-inferiority, parallel-group, randomized, open-label clinical trial enrolled UK adults hospitalized with neutropenic sepsis. Participants were randomly assigned to either switch to oral ciprofloxacin plus co-amoxiclav within 12-24 hours or to continue intravenous treatment for at least 48 hours. The primary outcome was a composite measure of treatment failure, 14 days after randomization. The non-inferiority margin was 15%. RESULTS: There were 129 participants from 16 centres and 125 were assessed for the primary outcome. Of these, 113 patients completed protocolized treatment and comprised the per-protocol population. In total, 9 (14.1%) of 64 patients in the standard care arm met the primary end point, compared with 15 (24.6%) of 61 in the early switch arm, giving a risk difference of 10.5% (1-sided 95% CI, -∞% to 22%; p 0.14). In the per-protocol population, 8 (13.3%) of the 60 patients in the standard care arm met the primary end point, compared with 9 (17%) of 53 in the intervention arm giving a risk difference of 3.7% (one-sided 95% CI, -∞% to 14.8%; p 0.59). Duration of hospital stay was shorter in the intervention arm (median 2 [inter-quartile range (IQR) 2-3] vs. 3 days [IQR 2-4]; p 0.002). DISCUSSION: Although non-inferiority of early oral switch was found in the per-protocol population, the intervention was not non-inferior in the intent-to-treat population.


Assuntos
Neutropenia , Sepse , Adulto , Humanos , Antibacterianos , Ciprofloxacina/uso terapêutico , Sepse/tratamento farmacológico , Sepse/induzido quimicamente , Neutropenia/complicações , Resultado do Tratamento
13.
Sci Justice ; 63(6): 755-762, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38030345

RESUMO

Validation is particularly important in forensic science. Each process utilised by a forensic laboratory will undergo validation to ensure it is functioning as expected. Some pieces of equipment (hardware) will be simple to validate, and this will be conducted regularly. However, many commonly employed fingermark enhancement reagents, such as ninhydrin and 1,2-Indandione, do not have clearly defined and robust validation parameters. To that end, artificial fingermark solutions, particularly amino acid solutions, have previously been investigated as a controlled validation method, via deposition onto a substrate. Whilst amino acid reagents are important, there is also a wider group of latent fingermark constituents (targets) that require the use of other enhancement reagents within the forensic laboratory. The work presented herein seeks to expand on the concept of amino acid printing, by exploring the possibilities of depositing a sebaceous solution matrix, thereby facilitating the testing of reagents such as Oil-Red-O and Physical Developer. In addition, we present a method that extends capabilities beyond fingermark enhancement reagents for porous substrates, by developing a methodology that enables process validation of the cyanoacrylate fuming technique to be easily facilitated. These simple and effective solutions have the capacity to serve as a crucial process validation check within the laboratory validation workflow.


Assuntos
Dermatoglifia , Ninidrina , Humanos , Indicadores e Reagentes , Ninidrina/química , Aminoácidos/química , Medicina Legal
14.
Opt Express ; 31(21): 33850-33872, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859156

RESUMO

Future satellite-to-ground optical communication systems will benefit from accurate forecasts of atmospheric optical turbulence; namely for site selection, for the routing and the operation of optical links, and for the design of optical communication terminals. This work presents a numerical approach based on the Weather Research and Forecasting software that enables continuous forecast of the refractive index structure parameter, C n2, vertical profiles. Two different C n2 models are presented and compared. One is based on monitoring the turbulent kinetic energy, while the other is a hybrid model using the Tatarskii equation to depict the free atmosphere region, and the Monin-Obukhov similarity theory for describing the boundary layer. The validity of both models is assessed by using thermosonde measurements from the Terrain-induced Rotor Experiment campaign, and from day and night measurements of the coherence length collected during a six-day campaign at Paranal observatory by a Shack-Hartmann Image Motion Monitor. The novelty of this work is the ability of the presented approach to continuously predict optical turbulence both during daytime and nighttime, and its validation with measurements in day and night conditions.

17.
Inorg Chem ; 62(40): 16564-16573, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37768147

RESUMO

The ternary oxides, Li2NpO4 and Li4NpO5, were synthesized under mild hydrothermal conditions using concentrated LiOH solutions containing NpO2(NO3)2. The reactions resulted in the formation of single crystals of both compounds, enabling the determination of their single crystal structures for the first time. Exploration of the synthetic phase space demonstrates that the resulting neptunate phases are dependent on the concentration of LiOH, transitioning from Li2NpO4, containing a typical octahedral neptunyl geometry with two shorter Np≡O bonds, at lower LiOH concentrations to Li4NpO5 with two long and four short Np-O bonds under saturated solution conditions. Reactions exploring the same synthetic conditions are also reported for uranyl(VI) for comparison. Raman spectra of the compounds were collected and analyzed to evaluate the Np-O bonding in these compounds.

18.
Inorg Chem ; 62(41): 16770-16781, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37775335

RESUMO

An exploration of the synthetic and structural phase space of rare earth hybrid double perovskites A2B'BX6 (A = organocation, B' = M+, B = M3+, X = molecular bridging anion) that include X = NO3- and B' = alkali metal is reported, complementing earlier studies of the [Me4N]2[KB(NO3)6] (B = Am, Cm, La-Nd, Sm-Lu, Y) (Me4N = (CH3)4N+) compounds. In the present efforts, the synthetic phase space of these systems is explored by varying the identity of the alkali metal ion at the B'-site. Herein, we report three new series of the form [Me4N]2[B'B(NO3)6] (B = La-Nd, Sm-Gd; B' = Na, Rb, Cs). The early members of the Na-series crystallize in the trigonal space group R3̅ from La to Nd where a phase transition occurs in the phase between 273 and 300 K, going from R3̅ to the high-symmetry, cubic space group Fm3̅m. The preceding trigonal members of the Na-series also undergo phase transitions to cubic symmetry at temperatures above 300 K, establishing a decreasing trend in the phase-transition temperature. The remainder of the Na-series, as well as the Rb- and Cs-series, all crystallize in Fm3̅m at 300 K. The temperature-dependent phase behavior of the synthesized phases is studied via variable-temperature spectroscopic methods and high-resolution powder X-ray diffractometry. All phases were characterized via single-crystal and powder X-ray diffraction and Fourier transform infrared (FT-IR) and Raman spectroscopic methods. These results demonstrate the versatility of the perovskite structure type to include rare earth ions, nitrate ions, and a suite of alkali metal ions and serve as a foundation for the design of functional rare earth hybrid double perovskite materials such as those possessing useful multiferroic, optical, and magnetic properties.

19.
New Phytol ; 240(4): 1449-1466, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37598305

RESUMO

N-linked protein glycosylation is a conserved and essential modification mediating protein processing and quality control in the endoplasmic reticulum (ER), but how this contributes to the infection cycle of phytopathogenic fungi is largely unknown. In this study, we discovered that inhibition of protein N-glycosylation severely affected vegetative growth, hyphal tip development, conidial germination, appressorium formation, and, ultimately, the ability of the maize (Zea mays) anthracnose pathogen Colletotrichum graminicola to infect its host. Quantitative proteomics analysis showed that N-glycosylation can coordinate protein O-glycosylation, glycosylphosphatidylinositol anchor modification, and endoplasmic reticulum quality control (ERQC) by directly targeting the proteins from the corresponding pathway in the ER. We performed a functional study of the N-glycosylation pathway-related protein CgALG3 and of the ERQC pathway-related protein CgCNX1, which demonstrated that N-glycosylation of ER chaperone proteins is essential for effector stability, secretion, and pathogenicity of C. graminicola. Our study provides concrete evidence for the regulation of effector protein stability and secretion by N-glycosylation.


Assuntos
Colletotrichum , Zea mays , Glicosilação , Zea mays/microbiologia , Retículo Endoplasmático , Doenças das Plantas/microbiologia
20.
Biology (Basel) ; 12(8)2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37627019

RESUMO

Fish aquaculture is a rapidly expanding global industry, set to support growing demands for sources of marine protein. Enhancing feed efficiency (FE) in farmed fish is required to reduce production costs and improve sector sustainability. Recognising that organisms are complex systems whose emerging phenotypes are the product of multiple interacting molecular processes, systems-based approaches are expected to deliver new biological insights into FE and growth performance. Here, we establish 14 diverse layers of multi-omics and clinical covariates to assess their capacities to predict FE and associated performance traits in a fish model (Oncorhynchus tshawytscha) and uncover the influential variables. Inter-omic relatedness between the different layers revealed several significant concordances, particularly between datasets originating from similar material/tissue and between blood indicators and some of the proteomic (liver), metabolomic (liver), and microbiomic layers. Single- and multi-layer random forest (RF) regression models showed that integration of all data layers provide greater FE prediction power than any single-layer model alone. Although FE was among the most challenging of the traits we attempted to predict, the mean accuracy of 40 different FE models in terms of root-mean square errors normalized to percentage was 30.4%, supporting RF as a feature selection tool and approach for complex trait prediction. Major contributions to the integrated FE models were derived from layers of proteomic and metabolomic data, with substantial influence also provided by the lipid composition layer. A correlation matrix of the top 27 variables in the models highlighted FE trait-associations with faecal bacteria (Serratia spp.), palmitic and nervonic acid moieties in whole body lipids, levels of free glycerol in muscle, and N-acetylglutamic acid content in liver. In summary, we identified subsets of molecular characteristics for the assessment of commercially relevant performance-based metrics in farmed Chinook salmon.

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